Capacitance Definition and 903 Threads

So I read a page where someone said they had put 18 400v 3900uF capacitors in parallel and that this came out to 5600 joules... Now I'm sure I am doing something wrong but when I did it out I only got 28.08 joules... I used this website...

Hi, I have a post layout extracted netlist, In which I am interested in input capacitance on clock pin, If i measure clock pin input capacitance on post layout extracted netlist, I am getting 1.58fF and when I measure the same in schematic, I am getting 0.6fF and I am able to find the paracitics...

Wes thu hal, I have been researching computer hardware aspects, and I have been recently looking at RAM types, particularly DRAM. I am think of making a simple model of it for a hobby. For a DRAM bit cell, does the capacitance value matter? What affects does it have if it is big or small, e.g...

Hi. The capacitance of an ideal plate capacitor (coaxial cable) goes to zero as the plate distance (outer radius) goes to infinity. This doesn't happen with concentric spheres as we let the outer radius go to infinity, hence a single sphere has a nonzero capacitance. What's the exact reason...

First, take the case of a winding with a regular capacitor connected to both terminals of the winding. When a moving magnetic field induces a voltage therein, the cap becomes charged and a current flows in the conductor while cap is charging, producing a magnetic field. Next, take the case of a...

i connected pin 4 and 8 to gnd and +5 v respectively .when pin 2 touches wood, or hand pin 1 is high. i understand skin is capacitive , but wood?

is there any way to fully neutralize a charged metal plate ? connecting it to metal body of relatively huge capacitance will make its charge negligible but not zero? is there any other way?

Is it possible to combine (possibly infinite) capacitors and inductors to get a total impedance which is independent of frequency. If so, how?

Hi, My setup for measuring parallel plate capacitance consists of an LCR meter and a parallel plate test fixture. The area of the parallel plates is much larger than the area of the samples I am measuring. From what I've seen in literature, and my physics classes, the sample area should be...

Homework Statement Basically I have to convert from Gaussian Units in a Transmission Line Experiment. I don't get what the point of expressing Capacitance in cm is and I find this very confusing. Homework Equations The equation I've been given is C'=Q'/V=w/4πh, (1) where the prime denotes "per...

Hi everyone, 1. Homework Statement It takes 18 J of energy to move a 0.30-mC charge from one plate of a capacitor to the other. How much charge is on each plate? Homework Equations -We/q = ΔV C = Q/V The Attempt at a Solution -18J/0.3.10-3 C * 15.10-6 F = Q Q = -0.9 C The problem is...

Homework Statement Ive got these questions and I am not quite sure where to start. if someone could point me to the equations to use for Q1 and Q4, id appreciate it. As for Q2 and Q3, I need help with how to determine if its in series or parallel and how to properly add them. Homework...

Homework Statement The equivalent capacitance of the capacitors shown in Figure 21-41 is 9.22 microFarads. Find the value of capacitance C.Homework Equations Ok so this has to deal with Ceq, and it is a combonation of series and parallel circuits. Knowing this, I can use for series...

It's just that I've never properly sorted this confusion of mind, so i would like to sort it out so it 2 different capacitors are in series with a resistor: (let's say 0.15F, 0.45F, 150M ohm) 1. both current and voltage drops exponentially 2. capacitance on capacitors remain same over time? 2...

Can somebody confirm if this is correct? I'm trying to use a wye-delta transformation on capacitors to solve for equivalent capacitance, but to be super-precise, I want to put capacitance in terms of resistance. I = C*(dV/dt) V = IR, so I = V/R V/R = C*(dV/dt) (V*dt) = R*C* dV Integrate both...

Homework Statement Homework EquationsThe Attempt at a Solution Here are two questions. I'm stuck on question 1, and need someone to check question 2. For the first question I see C2, C3, and C4 in parallel, so Ceq of those 3 are C2 + C3 + C4 = 3C but now how do I continue? seems like the 3...

...were infinite? In other words: is capacitance a reflex of the finitude of the speed of light? Please elaborate. Thanks a lot in advance.

I'm trying to make a simple capacitance sensor to use with my controller. Do I need two resistors? And where do I place them? I drew a circuit diagram of what I'm thinking so far.

1. In above image an insulated metal plate has been placed inside Earth (soil), and an voltage is applied between plate and Earth groung what will be the capacitance here?? 2. one plate is the metal and the other plate is entire earth, so it is a big assymetrical Capacitor or What? all...

Homework Statement A parallel plate capacitor having plates of area S and plate separation d, has capacitance C1 in air. When two dielectrics of different relative permittivities ( ε1=2 and ε2=4) are introduced between the two plates as shown in the figure, the capacitance becomes C2. the ratio...

Homework Statement A parallel plate capacitor of area A and separation d is fully charged so that the charge on the top plate is Q. The battery is disconnected and two dielectric slabs of dielectric constant k are inserted with an air gap between them. Each region takes up one third of the...

Hi Friends, I am trying to find variation in capacitance between two plates with applied body load. I defined an air box around the plates. Now I'm trying with electromechanics physics for applying body load and finding capacitance. I defined the two plates as linear elastic material. Applied...

Homework Statement Explain why a capacitor will discharge, although very slowly when there is high internal resistance? Homework Equations V=IR Q=V/C The Attempt at a Solution I am confused slightly by internal resistnace. Does that refer to regular resistance. From that high internal...

Homework Statement The plates of a parallel plate capacitor of capacitance C0 are horizontal. Into the gap a slab of dielectric material with K=2 is placed, filling the bottom half of the gap between the plates. What is the resulting new capacitance? Homework Equations C = Q/V = κɛ0A/d The...

Homework Statement Given ZV1 = ZV2 = 100Ω, ZCCV = ZCV = 2000/j = -2000j, and VV/VC = 0.04789. I'm trying to get the given VV/VC result. Homework Equations I know that 1/ZV = 1/ZV1 + 1/ZV2 + 1/ZCV VV = ZV / (ZV + ZCCV) * VC The Attempt at a Solution 1/ZV = 1/ZV1 + 1/ZV2 + 1/ZCV = 1/100 +...

Hi guys, I've been trying to figure out how the capacitance of two microstrips, separated a distance d, are influenced by the presence of a dielectric. The dielectric will be a height (h) above the strips and has restricted movement. Using the electric potential I am able to derive a function...

Homework Statement Energy in the circuit remains constant. When the current is flowing, the energy stored is all stored in the inductor. When the current stops flowing, it is because all the energy is stored in the capacitor. Find the fraction of energy stored in the inductor when half of the...

Homework Statement Two identical parallel-plate capacitors, each with capacitance 10.0 μF, are charged to potential difference 50.0 V and then disconnected from the battery. They are then connected to each other in parallel with plates of like sign connected. Finally, the plate separation in...

Homework Statement Two parallel plates are connected to a battery which maintains a constant potential difference of 12.0 V. The distance between the plates can be varied and there are three plates of different dielectric materials available: rubber (0.40 mm, κ = 6.7), glass (4 mm, κ = 7) and...

Homework Statement Consider the situation shown in the figure. The width of each plate is b. the capacitor plates are rigidly clamped in the lab and connected to a battery of emf E. All surfaces are frictionless. Calculate the value of M for which the dielectric will stay in equilibrium...

Homework Statement Find the potential difference between points a & b. Diagrams attached below. I have doubts in part (b) and (c). Homework Equations Q = CV, kirchhoff's laws The Attempt at a Solution I honestly don't get how the current can flow in opposite directions in part(b). if we...

Homework Statement This is not necessarily a homework question, just a conceptual one. I was reading up on capacitors, and an example said that a 25uF capacitor has TWICE the impedence of a 50uF capacitor. Can someone explain what this means? I would have thought that a capacitor with higher...

Homework Statement imgur link: http://i.imgur.com/TWB5rRu.png Homework EquationsThe Attempt at a Solution I can find the equivalent capacitance, 10F, but I'm not really sure how to find the equiv. Thev. voltage. I figured that with the voltage source present, half the voltage will be lost...

Homework Statement Fig. 25-39 shows a 12.0 V battery and four uncharged capacitors of capacitances C1 = 1.00 µF, C2 = 2.00 µF, C3 = 3.00 µF, and C4 = 4.00 µF. If only switch S1 is closed, what is the charge on (a) capacitor 1, (b) capacitor 2, (c) capacitor 3, and (d) capacitor 4? (figure at...

A capacitor has a capacitance C and is charged using a battery. After disconnecting the battery the two plates are separated until they are twice as far apart as originally. What happens to the voltage across the capacitor? I think answer should be voltage increases . As battery has been...

Homework Statement Find the capacitance of the circuit if C1 = 10.3, C2 = 41.1, C3 = 95.5, C4 = 299.9, and C5 = 525.7, with all the units being in microfarads. Homework Equations 1/Series Ctotal = 1/c1 + 1/c2 ... Parallel Ctotal = C1 + C2 + ... The Attempt at a Solution I tried to combine all...

Homework Statement Please calculate the equivalent capacitance if C1 = 10.3 microfarads, C2 = 41.1 microfarads, and C3 = 95.5 microfarads in the diagram. Homework Equations 1 / Ctotal for Parallel = (1/C1) + (1/C2) + ... Ctotal for Series = C1 + C2 + ... The Attempt at a Solution So I tried...

Hey everyone! I have a doubt that relates to energy stored in different capacitors (when they're in a circuit). I understand how in capacitors connected in parallel, the capacitor with the biggest capacitance stores the most energy because: E = 1/2 CV2 So naturally the bigger the capacitance...

Homework Statement Homework Equations Series: 1/Ceq=1/C1+1/C2 Parallel: Ceq =C1+C2 The Attempt at a Solution So to find the equivalent resistance do I short (put a wire through the open terminals) the circuit and start adding up the capacitors? Once I do that do I just create a new circuit...

Homework Statement I am having trouble simplifying a circuit of capacitors that I was given. I am asked to determine the equivalent capacitance of the combination below (attached photo). Homework Equations Capacitors in series: 1/Ceq = 1/C1+1/C2+... Capacitors in parallel: Ceq = C1 + C2 +...

in deriving the capacitance of a parallel plate capacitor why do we take the field between the capacitors as σ/∈ and not 2σ/∈,when there are two plates and in the region between the capacitors, field must add up so shouldn't it be 2σ/∈?

Speaking just of long straight wires, not loops, coils or solenoids. Ideal wires have no resistance. Of course they would have no capacitance. And real wires have some very small amount of inductance, no? Firstly, would an ideal wire have some ideal nonzero inductance? Why/why not? After all...

Please explain in detail how to derive formula for capacitance of spherical capacitor?

Im trying to compare, visually in my head, the difference between transmitting data vs something like radio or microwaves vs how inductance and capacitance. I understand that the way the wave is modulated for example, AM or FM, can be interpreted as 0s or 1s. Im trying to compare this to...

Homework Statement If 100 volts of potential difference is applied between a and b in the circuit .Find the potential difference between c and d. 2. Homework Equations For Equivalent Capacitance in series ##\frac{1}{C}##=##\frac{1}{C_1}##+##\frac{1}{C_2}##For Equivalent Capacitance in...

Homework Statement Find the equivalent capacitance of the combination between A and B in the figure. Homework Equations For Equivalent Capacitance in series ##\frac{1}{C}##=##\frac{1}{C_1}##+##\frac{1}{C_2}##For Equivalent Capacitance in parallel ##C##=##C_1##+##C_2##... The Attempt at a...

Mentor's note: Post moved to new thread since it's a new problem. One more problem Homework Statement Find the equivalent capacitance between A and B. Homework Equations The Attempt at a Solution I think all the Capacitors are in series but according to my book only three capacitors are in...

Homework Statement I need to find equivalent capacitance between A and B. Homework Equations ##C##=##C_1##+##C_2##... It was for parallel connection. ##\frac{1}{C}##=##\frac{1}{C_1}##+##\frac{1}{C_2}##... It was for series connection. The Attempt at a Solution I tried to solve the problem...

Hey, guys! I had a brief electromag question. If capacitance is defined as the amount of charge that can be stored in a capacitor per unit of potential difference, then technically can capacitors made from insulators still have a capacitance? The problem I'm considering is calculating the...

First question; I was measuring capacitance in various guitar pickup coils that have the same diameter of wire with an Extech LCR Meter, and it seemed to be that the more winds, the higher the inductance as expected, but I would get lower capacitance readings, too, both at 120 kHZ and 1k Hz...